冠動脈内視鏡レーザー手術 : 問題点と解決法

抄録

The endoscopic coronary laser angioplasty system using excimer laser thin diameter endoscope has been developing.
In order to improve the transmitted energy through the laser fiber, long pulse excimer laser was used for the experiment. This laser could oscillate 308nm wavelength (XeCl) with maximum I 50m.1 per pulse energy and 100ns pulse duration.
In order to improve the bending function at the tip of the endoscope. the endoscope, which had 4 directional bending function at the tip and had one channel for the laser fiber, was developed and evaluated using organized thrombus inside the goat's carotid artery which was made beforehand by the interposition of artificial graft with I cm length.
Using this long pulse excimer laser, the transmitted laser energy was improved to be maximum 30mJ/pulse and average 15mJ/pulse using the optical fiber for ultra violet laser transmission with 400μm core diameter. The energy was enough to destruct the atheroma with non-contact irradiation.
The developed endoscope had 1.5mm diameter, 1.7mm diameter at the tip and 150cm inserting length. Th endoscope had 4 directional bending function with 10-20° for each direction. The laser could be scanned to organized thrombus to destructed through this endoscope. This endoscope improved the scanning ability of laser irradiation. As the endoscope had small diameter enough to attach the coronary artery, it is possible to perform the experiment with coronary artery for the next step.